Isolated singularities of mappings with the inverse Poletsky inequality

  • E.A. Sevost'yanov Zhytomyr Ivan Franko State University, Zhytomyr, Ukraine; Institute of Applied Mathematics and Mechanics of NAS of Ukraine, Slavyansk, Ukraine


The manuscript is devoted to the study of mappings
with finite distortion, which have been actively studied recently.
We consider mappings satisfying the inverse Poletsky inequality,
which can have branch points. Note that mappings with the reverse
Poletsky inequality include the classes of con\-for\-mal,
quasiconformal, and quasiregular mappings. The subject of this
article is the question of removability an isolated singularity of a
mapping. The main result is as follows. Suppose that $f$ is an open
discrete mapping between domains of a Euclidean $n$-dimensional
space satisfying the inverse Poletsky inequality with some
integrable majorant $Q.$ If the cluster set of $f$ at some isolated
boundary point $x_0$ is a subset of the boundary of the image of the
domain, and, in addition, the function $Q$ is integrable, then $f$
has a continuous extension to $x_0.$ Moreover, if $f$ is finite at
$x_0,$ then $f$ is logarithmic H\"{o}lder continuous at $x_0$ with
the exponent $1/n.$


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Як цитувати
Sevost’yanov, E. (2021). Isolated singularities of mappings with the inverse Poletsky inequality. Математичні студії, 55(2), 132-136.